index.php

См. документацию.

<?
require($_SERVER["DOCUMENT_ROOT"]."/bitrix/modules/main/include/prolog_before.php");
$APPLICATION->SetTitle("Оплата заказа");
?><?$APPLICATION->IncludeComponent(
    "bitrix:sale.order.payment",
    "",
    Array(
    )
);?><?require($_SERVER["DOCUMENT_ROOT"]."/bitrix/modules/main/include/epilog_after.php");?>